Valve mechanism of internal-combustion engines



H. L. MILNER AND A. R. BEEBY. VALVE MECHANISM OF INTERNAL COMBUSTION ENGINES.

APPLICATION FILED SEPT. 2h I915.

Patented May 11, 1920.

2 SHEET SSHEET I.

H. L. MILNER AND A. R. BEEBY.

VALVE MECHANISM OF INTERNAL COMBUSTION ENGINES. APPLIQATION man SEPT. 21. 1915.

1,339,406. Patented y 11, 1920.

2 SHEETS-SHEET 2.

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HARRY LAWLEY IV IILNER, 0F

MANCHESTER, AND ALFRED RICHARD BEEBY, OF SOUTH FABNBOROUGH, ENGLAND.

VALVE MECHANISM OF INTERNAL-COMBUSTION ENGINES. I

Specification of Letters Patent.

Patented May 11, 1920.

Application filed September 21, 1915. Serial No. 51,860.

To all whom it may concern:

Be it known that we, HARRY LAWLEY MIL- NER and ALFRED RICHARD BEEBY, subjects of His Majesty the King of England, residing at Manchester, in the county of Lancaster, and South Farnborou h, in the county of Hants, respectively, I ingdoin of England, have invented certain new and useful Improvements in the Valve Mechanism of Internal-Combustion Engines, of which the following is a specification.

This invention relates to improvements in the valve'mechanism of internal combustion engines, and more particularly to engines of the type in which the cylinder or cylinders rotate about a fixed crank-shaft-such'as in the Gnome engine. The improvements are also applicable to any type of radial rotary cylinder engines in which the explosive mixture inlet valves are situated in and carried by the heads of the pistons, and to stationary, but not necessarily radial, cylinder engines by arranging the inlet valves in the piston heads as before. I In radial rotary cylinder engines of the kind above-mentioned it has been proposed to keep the valve normally closed by means of a coiled spring mounted on its stem, and to positively and mechanically operate and open said valve by means of a tappet rod slidably mounted in the corresponding connecting rod and having a shoeor runner pivotally mounted on its lower end and engaged in a cam groove formed in a cam secured on the corresponding crank of the crank shaft, said cam being common to and adapted to operate the inlet valves of all of the engine cylinders.

In the improved valve mechanism provided according to the present invention the tappet rod is of a resilient and extensible construction, that is,it is formed in sections which are normally held in extended relationship by opposed springs, the tappet rod is operated by the single external cam surface of a cam, and the upper valve-operating end of said tappet rod is of annular or ring formation and operates and opens the valve through the intermediation of a pivoted le- 7 ver.

In the accompanying drawings Figure 1 is a partly sectional elevation showing a suitable manner of carrying out the invention in connection with a Gnome rotary cylinder engine, and

Fig. 2 is a similar view on a plane at right angles'to Fig. 1.

A cam holder H is fitted on the crank web of the engine and to this holder is fixed a cam C of any desired shape. The single external surface C of the cam is adapted to operate a roller R which is carried in any suitablemanner in one end of a tappet rod section S which is reci rocated andguided in a bracket Gr secure on the connecting rod U of the engine. Over the other end of the rod section S is fitted a sleeve T which forms the other section of the sectional tappet rod and is adapted to be re ciprocated and guided in a bracket G which bracket is also secured on the connecting rod U just below the gudgeon pin P which is fitted in the piston head in which isprovided the usual induction valve V. The outer and upper end T of the sleeve T is of annular or ring formation through which passes the gudgeon pin P and the connecting rod end U. This I formation of the valve-operating end of the tappet rod avoids the necessity of slotting the gudgeon pin and the connecting rod end to accommodate the tappet rod. The inner periphery of the tappet rod end T is adapted to normally rest on the connecting rod end, but when raised said end T is adapted to actuate one end of a motion transmitting lever L passing under the stem of the induction valve V and pivoted at the other end to a suitable bracket K secured to the induction valve guide X which is suitably slotted to receive the said lever. A flange T is provided on the inner or lower end of the sleeve T, and between this flange and the lower end of the bracket G guiding the sleeve is mounted a coiled spring S which is adapted to retain the sectional tappet rod S, T, T in its normal lowcred and inoperative position. Abutting on the flange T and surrounding the rod section S is another coiled spring S which is adapted to be compressed upon the movement of the roller R upon the cam C, and re siliently connects the tappet rod section S to the section T and T.

In operation, at the commencement of the induction, the roller R riding on the cam surface C raises the section S of the flexible tappet rod and compresses the lower coiled spring S. When the force exerted by the spring S is sufficient to overcome the pressure of the upper coiled spring S and of the pivot pin, a tappet rod slidably mounted on springs Z and weights Y of the valve'V,'theduction valve, and a connecting rod for the tappet rod section T and T the lever L and the valve are lifted and the latter remains off its seat during the induction stroke. Compression then takes place, the valve being closed. Toward the end of the compression stroke the cam C again comes into operation, but, owing to the compression and explosion pressure in the cylinder the valve remains closed, the lower spring S not exerting sufficient lifting force upon the sleeve T to overcome the pressure in the cylinder. Thus the valve opens during the induction stroke only.

Thus it will be seen that there is no necessity for half speed gear for the cam when the invention is applied to engines having rotary cylinders. When the invention is applied to engines having stationary cylinders the cam would be rotated by suitable half speed gearing.

It will be understood that each connecting rod of a multiple cylinder engine would be provided with a resilient and extensible tappet rod and roller, and all the rods be operated by a single cam. p

The valve mechanism provided by the invention is designed to obtain a semi-automatic action of the induction valve, 1'. 6., the valve is adapted to operate automatically in the event of the tappet rod being removed for repairing or other purposes.

The balance weights Y and springs Z are of a known arrangement and are provided in a standard design of the Gnome engine to normally hold the valve upon its seat. The present invention therefore only resides in the provision and attachment of the improved tap'pet mechanism to the engine.

If desired, in rotary'cylinder engines, a weight or weights may be provided to assist in normally maintaining the parts of the tappet rod in balanced condition and in their inoperative or lowered positions, said weight or each of same being pivoted upon the guide G and having an arm projecting through a slot in the latter into a slot or recess formed in the side of the sleeve T.

What we claim as new and desire to secure by Letters Patent of the United States 151- 1. The combination with a cylinder, a

" crank element, a piston head having an induction valve, and a connecting rod for the crank element and the piston, of an outer the connecting rod exteriorly thereof and provided with an outer terminal portion of ring formation surrounding the said pivot pin, meansfor operating the tappet rod, and means actuated by the said outer terminal portion of the tappet rod for opening the valve. v

2. The combination with a cylinder, a crank element, a piston head having an induction valve, and a rod connecte crank element and the piston, of an outer pivot pin, a tappet rod slidab-ly mounted on the connecting rod exteriorly thereof and provided with an outer terminal portion ofring formation surrounding the said pivot pin, means for operating the tappet rod, and means including a pivoted lever actuated by the outer terminal portion of the tappet rod for opening the valve.

3. The combination with a cylinder, a crank element, a piston head having an induction valve, and a connecting rod for the crank element and the piston, of an outer pivot pin,'inner' and outer guides arranged exteriorly of and carried by the connecting rod, a tappet rod composed ofinner and outer telescopic sections operating in .the said guides, the outer section being tubular and provided at its inner end with a flange, coiled springs disposed on the said sections atthe inner and outer sides of the said flange for yieldably holding the sections in ex tended relation, the outer section having a terminal portion of ring formation surrounding the "said pivot pin, a cam for operating the tappet rod, and means including a pivoted lever actuated by the said terminal portion of the outer section of the tappet rod for opening the valve.

'4. A tappet rod for valve mechanisms of internal combustion engines, adapted to be mounted on a connecting rod, comprising inner and outer telescopic sections movable 7 relative to one another, the outer sectionbeing tubular and provided at its inner end with a flange and'at its outer end terminating into an annular ring shaped portion, the inner section being solid and sliding with- I in said tubular-outer section, coiled springs disposed on the said sections at opposite sides of said flange for yieldingly holding the sections in extended relation, and a roller mounted on the free end of the inner section.

5. The combination with a cylinder, a crank element, a piston head, having an in duction valve, and a connecting rod for the crank element and the'piston, o-f'an outer pivot pin, a resilient tappet rod slidably 1'15 mounted on the connecting rod and provided with an outer terminal portion of ring. formation surrounding the said pivot pin, means actuated by the said outer terminal portion of the tappet rod for opening the valve, and a cam secured to the crank ele- .ment for operating the resilient tappet rod,

whereby said tappet rod is actuated upon every revolution of said cam and the said valve opened. only upon every other revolution of said cam.

6. The combination with a cylinder, a crank element, a piston head havin an into the crank element and having pivotal connection with the piston head, of a resilient tappet rod having operative connection with said rod and provided with means movably embracing said pivotal connection adapted to open the valve, and a cam secured to the crank element for operating said tappet rod, whereby said tappet rod is actuated upon every revolution of said cam, and the said valve opened only upon every other revolution of said cam.

7. The combination with a cylinder, a crank element, a piston head having an induction valve, and a connecting rod for the crank element and the piston, of a pivot pin connecting the connecting rod and the piston, a tappet rod composed of telescoping sections slidably mounted on the connecting rod with the outer section of the tappetrod provided with an outer opened terminal portion surrounding said pivot pin with its open portion of greater diameter than the cross section of said pivot pin, resilient and compressible means embracing the tappet rod, and a cam secured to the crank element for operating the tappet rod to force the outer open end of the outer section of the tappet rod into operative engagement with the induction valve so as to open the latter.

In testimony whereof we have hereunto signed this specification.

HARRY LAWLEY MILNER. ALFRED RICHARD BEEBY. 

